Argentous rectifier



Jan. 3, 1950 M. LAZARUS 2,493,076

ARGENTOUS RECTIFIER Filed April 23, 1948 IIIIIIIIIIIAI:II:; IIIIIIIIIIA'A INVENTOR 1 M5 Yff? 4424205 BY Lam/Z mww.

ATTORN EY Patented Jan. 3, 1950' UNITED STATES PATENT OFFICE ARGENTOUS RECTIFIER Meyer Lazarus, Forest Hills, N. Y.

Application April 23, 1948, Serial No. 22,800

2 Claims.

My invention relates to improvements in dry disk rectifiers, and it consists in the novel features which are hereinafter described.

One of the objects of my invention is to reduce leakage of current in the inverse direction of a rectifier.

Another object is to increase the efilciency of rectification.

A further object is to reduce the amount of scrap, i. e. to reduce the number of defective elements when the rectifier discs are tested.

A still other object is to increase the'resistance in an inverse direction of a rectifier without affecting the resistance to the flow of current in a forward direction.

Another object of my invention is to produce an improved argentous rectifier comprising a layer of silver and cuprous oxide formed on a pure copper base.

A further object of my invention is to have the said layer of cuprous oxide and silver of varying density, i. e. of varying proportions of silver and cuprous oxide, the proportion of silver in the layer being greater near the copper base and least near the surface of the contacting terminal which is hereinafter described.

A still other object of my invention is to reduce to a minimum creep or gradual deterioration of the resistance of the rectifier elements in the inverse direction.

Another object of my invention is to enable the rectifying elements to withstand a higher operating voltage, whereby the number of elements in a rectifying unit may be reduced.

I attain these objects by the argentous rectifier which is illustrated in the accompanying drawings or by any mechanical equivalent or obvious modification of the same. i

In the drawings Fig. 1 is a cross-section on th line l-l of Fig. 2; and Fig. 2 is a plan view of my argentous rectifier, which consists essentially of three parts as follows:

II designates abase plate preferably of pure copper on which is formed a rectifying layer I! of unevenly distributed metallic silver and cuprous oxide, this layer having a light red color. A contacting terminal I3 is placed on the layer 12; The proportion of silver is greatest near the base I l and least near the contacting terminal ii.

The thickness of the layer I2 is exaggerated in the drawings for the sake of clearness.

The variation in the proportion of the metallic silver in the layer I2 is illustrated in Fig. 1 of the drawings by the profusion of dots in the layer near the base plate Ii and the relative scarcity of dots near the contacting terminal II.

The above described argentous rectifier may be employed with elements having a very small surface for rectifying minute currents for use in measuring instruments and also with elements having large areas for rectifying large currents for use in battery charging and for use in electric arcs.

In the process of making the above argentous rectifier I take a blank preferably of pure copper and have it plated with pure silver; thereupon I subject the plated blank to the oxidizing effect of hot atmospheric air in a suitable furnace to form the layer of fused silver and fused cuprous oxide on the exposed surface of the blank.

Either one or both faces of the blank may be oxidized.

In the said furnace the temperature of the air is sufficiently high to fuse silver and cuprous oxide, but not so high as to melt copper.

Variations are possible and parts of my invention may be used without other parts.

I claim as my invention and desire to secure by Letters Patent:

1. As an article of manufacture an argentous rectifier for alternating currents comprising a base of copper, a rectifying layer of metallic silver and fused cuprous oxide, the silver particles bein'g unevenly distributed in the layer, the portion of the layer which is nearest to the copper base having therein a larger proportion of silver particles and the portion of the layer which is blank.

further away from the copper base having therein a lesser proportion of silver particles, and a contacting terminal on the face of the rectifying layer which is remote from the copper base.

2. The process of preparing an argentous rectifier which consists in plating a pure copper blank with pure silver, thereupon subjecting an exposed face of the plated blank to the oxidizing effect of hot atmospheric air in a suitable furnace to form a layer of fused silver and fused cuprous oxide on the exposed surface of the blank, the

silver particles being unevenly distributed in the layer, the portion of the layer which is nearest to the copper base having therein a larger proportion of silver particles and the portion ofthe layer which is further away from the copper base having therein a lesser proportion of silver particles and completing the rectifier by applying a contacting terminal to the said layer on the face thereof which is remote from the copper LAZARUS.

REFERENCES CITED The following references are of record in the Number 

